The Company Eta Carinae Keeps: Stellar and Interstellar Content of the Carina Nebula

ABSTRACT

The remarkable, interrelated stellar and nebular constituents of η Carinae's habitat, the giant Carina Nebula (NGC 3372), are reviewed. They are relevant to the interpretation of η Car itself. They include some of the hottest and most massive O stars known, frequently in close multiple systems; mysterious nebular structures; recently recognized ongoing star formation; the most extreme high-velocity interstellar absorption-line profiles in the Galaxy; and both stellar and diffuse X-ray sources.